Goofs

At some point we see Patrick(Matthew Fox) getting bitten by a creature and you can see his wounded neck when he tries to disinfect it with alcohol. Later on, when they are being attacked by many creatures in the house scene, you can clearly see that his wound is not there.

The inside of the house with the elder couple is full of ice. This would never happen. Everything inside the house would just stay the same.

You can't give a dog chocolate. Especially that much chocolate over it appears a long period of time. Chocolate is highly toxic to dogs. The dog would be dead long before it was even bit and killed.

It is the cocoa in chocolate that is toxic. These are presumably milk chocolate chip cookies which would have a minimal cocoa percentage. Not healthy but not toxic.

Snow and ice looks artificial in many situation. The snow on the car would never look like depicted in the movie. Even it is supposed to be super cold there is hardly breath visible.